A Solid oxide fuel cell (SOFC) uses a solid oxide as an electrolyte where oxygen ions can pass through. The SOFC operates by reduction of oxygen gas at positive electrode to transport oxygen ions through the electrolyte membrane, and by oxidation of a fuel gas at the negative electrode. Typical electrolytes used include stabilized zirconia and doped ceria, like yttria stabilized zirconia (YSZ) and gadolinia doped ceria (GDC). Typical electrodes can be metal catalyst, like Pt, Ag, Ni, mixed ionic and electronic conducting oxides, as well as catalyst/electrolyte composites. The layered structure of the electrodes and the electrolyte are referred to as the membrane electrolyte assembly (MEA).
SOFC's are limited by low ionic conductivity and low catalytic activity, necessitating the SOFC to be operated at temperatures in excess of 700 degrees Celsius.
In one aspect, the power density of SOFC is determined by ohmic loss across the MEA stemming from slow ionic transport through electrolyte and concentration loss caused by limited gas interaction at the electrode reaction sites.
Accordingly, there is a need to develop an low-cost and easy to fabricate MEA structure, which reduces ohmic loss for better performances at a certain operating temperatures by increasing the electrode reaction surface area and reducing the thickness of the electrolyte to overcome the current limitations in the art.